The use of software engineering aids in the design of a structural finite-element analysis computer program for the CDC STAR-IOO computer is described. Since members of the design team came from diverse backgrounds, both the unique features of the CDC STAR computer and structural analysis concepts and computing requirements had to be understood before design began. Nested functional diagrams to aid in communication among team members were used, and a standardized specification format to describe modules designed by various members was adopted. This is a report of work in progress where use of the functional diagrams provided continuity and helped resolve some of the problems arising in this long-running part-time project.